The damage is done when that card is sent to an unsuspecting user, and they try to interact with it.

At first, the Messages app slows down. But then it stops responding to touch or taps entirely.

How to fix the problem:

The author of the prank has two possible solutions, but only one worked for me when I was trying to recreate the bug.

First, vincedes3 recommends visiting an HTML link on your iPhone. It is supposed to open a new text message, which frees up the Messages app enough for you to send and receive texts. Make sure to delete the thread with the cursed contact card.

But that didn’t work for me.

However, a different approach did work: Simply ask Siri on the affected phone to send a text message. The words don’t matter. Tap on the message on the Siri screen, and it will bring you into the Messages app, in which you can navigate again.